Colonic lipomas are benign adipose tumors which are usually submucosal. With the increase in the number of endoscopic procedures being performed, these tumors are often detected incidentally at colonoscopy. Although the risks of removing these tumors have been recognized, numerous reports have documented safe removal by snare electrocautery. We have reviewed the clinical outcome and the endoscopic and histopathologic features of seven lipomas that were endoscopically removed over a 5-year period. Four patients recovered uneventfully, while three patients (42.8%) developed colonic perforation after the polypectomy. In the latter group, the lipomas were significantly larger than they were in the patients who did not develop colonic perforation (1.9 +/- 0.4 and 4.2 +/- 0.7 cm, respectively; p = 0.048). Furthermore, the polypectomy specimens from those patients who developed perforation all contained significant muscularis propria. Lipomatous polyps that are identified at endoscopy to be greater than or equal to 2 cm in diameter and to have a limited pedicle are at the greatest risk for endoscopic perforation.